New research for financial comparison website, OneCompare.com suggests that just over half - 51 per cent - of mobile phone users have never switched providers despite being on uncompetitive deals.

OneCompare.com says users could save an average of £15-£20 but fail to do so because of inertia or lack of understanding.

The situation is compounded by mobile phone providers offering a multitude of tariff options making it impossible to compare various deals, says OneCompare.com director Anthony Ball.

"Mobile phones are one of the last areas of consumer finance where confusion still reigns supreme and this means many consumers are rooted firmly to deals from providers that we know are highly uncompetitive," says Ball.

"This research shows that cost is still a big issue in this market.

"Most people are paying more than £30 a month in bills.

"It's encouraging though to see that many people have got wise to the trick of being offered flashy new handsets in return for uncompetitive contract arrangements."

Of the people who have switched, Orange and Vodafone were the big losers. Mr Ball says this is unsurprising as these two providers hardly, if ever, reach the top three deals for available tariffs.